Pressure oil energy recovery device for work machines

摘要

PROBLEM TO BE SOLVED: To detect or predict a deterioration state of an accumulator at an early stage and encourage an operator to take an appropriate action. SOLUTION: An accumulator deterioration determination processing unit 47 of a controller 45 is from an elapsed time measuring unit 47A for measuring an elapsed time tx from the start of use of an accumulator 29 by a reset signal from a reset switch 44, and a pressure sensor 39 on the accumulator side. The operation number measurement unit 47B for measuring the number of operations of the accumulator 29, that is, the boom lowering number N after reset, the gas permeation amount estimation unit 47C for estimating the estimated gas permeation amount Qloss of the accumulator 29, and the accumulator 29. It is provided with an enclosed gas pressure estimation unit 47D for obtaining the estimated enclosed gas pressure Pgs of the gas chamber 29B, and an accumulator deterioration determination unit 47E for determining the deterioration status of the accumulator 29 and outputting the determination result. [Selection diagram] Fig. 6